The Comet


Welcome to the Wikispace page for the Comet, the oldest roller coaster in Hersheypark today!

external image Comet_008.jpg
Image from Wikipedia article on The Comet

Summary


The Comet is a wooden roller coaster that brings riders up a chain-lifted 84 foot rise, and then sends the car down 96 feet. The gravitational potential energy gained at the top of this first hill provides the kinetic energy that will carry the car through the rest of the ride. After the first hill, the hills get progressively smaller before going into a series of small "bunny hills" and subsequently braking to a stop back at the loading station.

Physics of the Ride

The Comet roller coaster is a prime example of the Law of Conservation of Energy. At the top of the 1st hill, the train solely has Gravitational Potential Energy. Because the 1st hill has the biggest drop, at the bottom it only has kinetic energy. It is absolutely necessary that on a roller coaster, the first hill is the largest drop. This is because if it is not, the car does not have enough energy to get up to the top of the next hill with out help. This sort of system continues throughout the entire length of any traditional coaster. Barring things like magnetic acceleration and such, the 1st hill must be high enough to provide the energy needed to travel along the coaster's entire length. This also means that no hill can be as large or larger than the first hill, unless a second winch is added to tow the cars. Otherwise, the cars would not have enough energy to make it over that hill, and would begin to reverse direction. This, of course, is potentially fatal to riders, and would need to be avoided at all costs during the architectural design stage of things. During a successful coaster run, the carts will accelerate down the initial hill, reaching full kinetic energy at the bottom, and then running a series of either hills or banking, throughout which the energy is conserved. This energy, of course, is basically the equivalent of the work done by the chain system that brought the carts up the first hill. At the end of the track, brakes are applied, using friction to dispense with the thusfar conserved energy, bringing the carts to a slow, rolling speed, at which point they re-enter the loading dock.


Data

*Riders per hour
1,100
*Length of Track
3360 feet
*Ride Duration
1 minute, 45 seconds
*Maximum Velocity
50 mph
Average Velocity
27 ft/sec
Height of First Hill
84' 2"
Height of Valley
4' 0"
Height of Second Hill
70' 6 1/2"
Horse Power of Motor
75
Area of Front Car

Length of Entire Train
8.6 square feet

40' 0"

*found on www.hersheypark.com

Calculations

PEi + KEi = PEf + KEf
For first hill: initial kinetic is 0 and final potential is 0
so PEi = KEf
mgy = .5mv^2
masses cancel out because it is assumed that no riders have been ejected from the train as it moved from top to bottom of the hill
gy = .5v^2
g = 9,.8 m/s^2 = 32 ft/s^2
32(height of 1st hill) = .5(velocity)^2

Picture Gallery
external image oldnew2.jpg

(www.ridezone.com)

external image 19353945.CarlisleHersheyParkJune28July12003173Webcopy.jpg
(www.pbase.com)

external image comet_1stdrop.JPG
(www.freewebs.com)

external image comet_outbound.JPG
(www.freewebs.com)

external image comethp3_devinolson.jpg
(www.coaster-net.com)
external image hers_com.jpg
(www.bannister.org)

external image 417008218_e9f6784021.jpg?v=0
(www.flickr.com)

external image 417007441_8c17f48c50.jpg?v=0
(www.flickr.com)